Security Incidents mailing list archives
Re: Tracking down the still infected hosts
From: "Kyle R. Hofmann" <krh () lemniscate net>
Date: Tue, 25 Sep 2001 12:28:49 -0700
On Tue, 25 Sep 2001 11:24:49 -0500, Tina Bird wrote:
According to Ryan Russell (who's been analyzing the worm code), Nimda doesn't honor redirects - it just checks the response it gets from a Web server to determine whether or not the server is vulnerable. It doesn't follow redirects. So what does this actually accomplish?
Actually, I'm not sure it accomplishes anything. I read the post saying that redirecting Nimda to 127.0.0.1 killed it or slowed it down, and I wrote and posted my redirection tool before I spent a lot of time watching Nimda's reaction to it. Now that I've let it run overnight, I'm convinced that it doesn't do any good. Nimda traffic on my machine has actually gone up, because now it doesn't stop--it just keeps pounding on me, gleefully ignorning the redirects. I've gotten about 1.44 HTTP connections per minute in the past six hours, primarily from two persistent machines, whereas yesterday, before I had written my tool, I got about 0.391 connections per minute spread out among a half-dozen or so machines. Since none of this is legitimate traffic (my machine hasn't run a web server in half a year), for machines that don't run web servers it's clearly less effective to send redirects than to simply refuse connections. I suspect that the same is true for web servers, as well. -- Kyle R. Hofmann <krh () lemniscate net> ---------------------------------------------------------------------------- This list is provided by the SecurityFocus ARIS analyzer service. For more information on this free incident handling, management and tracking system please see: http://aris.securityfocus.com
Current thread:
- Tracking down the still infected hosts Darren Windham (Sep 24)
- Re: Tracking down the still infected hosts Mike Lewinski (Sep 24)
- <Possible follow-ups>
- RE: Tracking down the still infected hosts Martinez, Simon (Sep 24)
- RE: Tracking down the still infected hosts Fulton L. Preston Jr. (Sep 24)
- RE: Tracking down the still infected hosts Ryan McDonnell (Sep 25)
- Re: Tracking down the still infected hosts Kyle R. Hofmann (Sep 25)
- Re: Tracking down the still infected hosts Tina Bird (Sep 25)
- Re: Tracking down the still infected hosts Skip Carter (Sep 25)
- Re: Tracking down the still infected hosts Kyle R. Hofmann (Sep 25)
- Re: Tracking down the still infected hosts Dale Lancaster (Sep 25)
- Re: Tracking down the still infected hosts Duncan Hill (Sep 25)
- Re: Tracking down the still infected hosts Josh Burroughs (Sep 25)
- Message not available
- Re: Tracking down the still infected hosts Nicole Haywood (Sep 25)
- Re: Tracking down the still infected hosts Ryan Russell (Sep 25)